The Sigma 15mm f/2.8 EX DG Diagonal Fisheye for Canon EF is a specialized ultra-wide prime lens that delivers a dramatic 180-degree diagonal field of view, filling the entire full-frame sensor with its signature curvilinear distortion. Released as part of Sigma’s premium EX series, it features a fast f/2.8 aperture ideal for low-light environments, astrophotography, and creative sports shooting. With a remarkably short minimum focusing distance of just 5.9 inches, photographers can get close to subjects to heavily exaggerate perspective, while its rugged build and integrated petal-type hood ensure durability in the field.